Kaolin-supported ZnO nanoparticle catalysts in self-sensitized tetracycline photodegradation: Zero-point charge and pH effects

Photocatalytic Degradation of Tetracycline by ZnO/γ-Fe2O3 Paramagnetic Nanocomposite Material

“…These evidences exclude the possibility of a charge separation at the ZnO and γ-Fe 2 O 3 interface, confirming that the two nanostructures cannot cooperate in the photodegradation process and the H 2 O 2 formation by water oxidation is unlikely. Finally, as reported in the literature [17], the two absorption bands at about 275 and 360 nm of an aqueous solution of tetracycline can be ascribed to the conjugated double-bond structures with two carbonyl groups and enolic groups, respectively [35]. The tetracycline absorption spectra, in the presence of ZnO/γ-Fe 2 O 3 catalyst, at the initial time and after 150 min of light irradiation are shown in Figure 6b.…”

“…Finally, as reported in the literature [ 17 ], the two absorption bands at about 275 and 360 nm of an aqueous solution of tetracycline can be ascribed to the conjugated double-bond structures with two carbonyl groups and enolic groups, respectively [ 35 ]. The tetracycline absorption spectra, in the presence of ZnO/γ-Fe 2 O 3 catalyst, at the initial time and after 150 min of light irradiation are shown in Figure 6 b.…”

“…In addition, AOPs allow mineralization of recalcitrant organic pollutants into green products with a rapid degradation rate under ambient temperature and pressure conditions [ 16 ]. ZnO and TiO 2 , the most used semiconductors in oxidation processes, have a band gap energy of about 3.2 eV and consequently, their excitation is limited to the ultraviolet (UV) radiation range [ 16 , 17 , 18 , 19 , 20 ]. However, ZnO nanoparticles are cheaper than TiO 2 ones and ZnO photon absorption efficiency at room temperature is higher that the light absorption properties of TiO 2 under the same conditions [ 17 ].…”

Synthesis of a plasmonic AgCl and oxygen-rich Bi24O31Cl10 composite heterogeneous catalyst for enhanced degradation of tetracycline and 2,4-dichlorophenoxy acetic acid

“…The 2,4-D scavenger degradation results show that the main reactive species responsible for the degradation are ˙O 2− and h + while the reactive species in TC degradation was the superoxide radical. This difference is attributed to the TC-sensitization that occurred whereby TC molecules are absorbed on the surface of the photocatalyst 56 possibly taking prevalence over the activity of holes during photodegradation. The results also reveal that hydroxyl radicals are not an important reactive agent in this degradation process.…”

Boosted Cr(VI) sorption coupled reduction from aqueous solution using quaternized algal/alginate@PEI beads

“…(FEI France, Thermo Fisher Scientific, Mérignac, France), coupled with an Oxford Inca 350 energy dispersive X-ray (EDX) micro-analyzer (Oxford Instruments France, Saclay, France). The pH point of zero charge (pH PZC ) of the beads was approached applying the so-called pH drift method (Zyoud et al, 2019). A fixed amount of sorbent (i.e., 0.05 g) was added to 25 mL of 0.1 M NaCl solution at different initial pH values (pH 0 , in the range of 1-12).…”